The present invention relates to a new and improved seal for a door on a combustion chamber of a fluid heater or boiler and to the method for sealing the door and to the kit that may be used to seal the door.
Most combustion chambers of fluid heaters include a rear door at the opposite end of the combustion/heat exchanger structure to allow access for service and assembly. During operation of these prior art heaters over a substantial length of time, the refractory in the rear door deteriorates due to the intensity of radiation and the impingement of combustion products. This deterioration results in the loss of refractory and poor performance of the unit due to increased heat losses in the area of the door. It is desirable that this deterioration of the refractory in the door and resultant heat loss be eliminated or substantially reduced. In addition, it is also desirable that a kit or similar device be available such that doors on existing heaters can be sealed in order to avoid deterioration of the refractory and resultant heat loss.